This is a fantasy adventure where the characters are the monsters! Your squad is besieging a civilised city, and you've been many moons in this mud. If the enemy don't get you the food will, or the officers. Or the ogres.
Fifteen events take your squad from the relative safety of their siege tower to the final assault on the walls. In between, you'll follow orders, no matter what they are.
Five PCs are provided with 5th Edition D&D stats. It's simplicity itself to use this scenario for any fantasy edition or rules, as it's heavy on the words and light on the numbers so you can make it your own.